1. Field of the Invention
The invention relates to a computer system. More particularly, the invention relates to a computer system configured to detect motion.
2. Description of the Related Art
An example of a computer system includes a conventional computer having conventional computer electronics, such as a central processing unit (CPU), a hard disc drive, an audio card and a video card. A mouse, a keyboard and a monitor are in most cases considered part of the computer.
Such a computer system typically processes text, graphics, voice or video. Often, the computer system includes a hard disc drive to handle the large amounts of data involved in these interactions. In addition, depending on the user""s specific applications, the computer system can be further connected to loudspeakers, a microphone and to a video camera. Conventional sound and video cards within the computer allow operation of these additionally connected devices.
Conventional computer systems often have an interface (e.g., a modem, network connection), that allows the user to send and receive electronic mail (e-mail) via a local network or the INTERNET. For instance, the computer system may be configured to xe2x80x9csurfxe2x80x9d the INTERNET, make telephone calls, send individual pictures, video clips, or play music from radio stations around the world.
When a user is not using the computer system, the computer system is switched off or running in an idle or stand-by mode. In the idle or stand-by mode, conventional computer systems typically display screen savers or perform other tasks that require a small fraction of the computer system""s performance. An example of such a task is waiting for incoming electronic mail or facsimiles.
In one embodiment, the invention uses the time when a user is away from a computer system to perform video surveillance of a viewing area. In other embodiments, the invention performs video surveillance of a viewing area as specified by a user. In particular, the invention uses video technology in a novel way to detect motion in a viewing area. Once the invention detects motion, embodiments of the invention can also perform a variety of predefined activities. For example, when motion occurs in a viewing area, the invention product can record the viewing area for security purposes, signal an alarm or notify a remote location.
In one embodiment, a video camera is connected to a video processing system. The video processing system converts the video data from the camera to encoded video segments that generally vary in size based on the amount of motion in the video camera""s field of view.
A processor averages the video segments to determine when sufficient motion exists in the field of view. In one embodiment, the processor calculates a weighted average which places greater emphasis on the more recent video segments. The processor then compares the weighted average to a threshold to determine when sufficient motion exists in the field of view.
In one embodiment of the present invention, a conventional video camera and a computer can be used as a security or monitoring system. This computer system is triggered by motion detected in front of the video camera. Once triggered, the computer system records both a video clip and sound, and can trigger an alarm or a notification. For example, a working parent can use the computer to receive an automatic notification that the children have returned home from school safely. Alternatively, an office worker can use the computer to determine who was looking for him while he was away from his desks. Under certain circumstances, the user may connect the system directly to the police or a private security system.
One aspect of the invention relates to a motion-detection system that detects motion in a field of view. The motion-detection system is configured to process encoded video data about the field of view to determine when sufficient motion exists in the field of view. The motion-detection system comprises a video camera that generates a series of video frames that represents a field of view in front of the video device.
The motion-detection system further comprising a video encoder in communication with the video frames. The video encoder is configured to process the video frames to generate encoded video frames wherein the size of the encoded video frames vary based on the amount of motion in the field of view.
A computer is in communication with the encoded video frames, the computer comprising a threshold value stored in a computer accessible storage medium. The computer further comprising a processor in communication with the encoded video data and the threshold value. The processor is configured to process the encoded video frames to determine a weighted average of at least a portion of the encoded video frames. The processor is further configured to detect motion when the weighted average exceeds the threshold value.
Another aspect of the invention relates to a motion-detection apparatus that comprises a series of video segments configured to vary in size based on movement in a field of view. The motion-detection apparatus further comprises a processor configured to process at least a portion of the video segments to determine an average. The processor is further configured to detect motion when the average exceeds a threshold.
Another aspect of the invention relates to an article of manufacture comprising a signal processing module stored in a computer accessible storage media and executable by a processor. The signal processing module is configured to calculate an average of multiple video segments that vary in size based on movement in a field of view. The signal processing module is further configured to detect motion when the average exceeds a threshold.
An additional aspect of the invention relates to a motion-detection apparatus that comprises a series of video segments configured to vary in size based on movement in a field of view. The motion-detection apparatus fierier comprises a means for processing at least a portion of the video segments to determine an average. The means also detecting motion when the average exceeds a threshold.
Another aspect of the invention relates to a method of detecting motion comprising the act of generating video data that represent a field of view and encoding the video data to generate encoded video segments that vary in size based on the amount of motion in the field of view. The method also comprising the acts of determining a weighted average of at least a portion of the encoded video segments and detecting motion when the weighted average equals or exceeds a threshold.
An additional aspect of the invention relates to a method of detecting motion comprising the act of receiving video segments that vary in size based on movements in a field of view. The method also comprising the act of calculating an average of at least a portion of the video segments. The method further comprising the act of detecting motion when the average exceeds a threshold.
Another aspect of the invention relates to a motion-detection system that transfers video segments stored in a buffer to a computer accessible storage medium when motion is detected in a field of view. The motion-detection system comprises a video camera with a field of view, the video camera configured to generate video data about the field of view.
The motion-detection system further comprising a video encoder configured to process the video data to generate video segments that vary in size based on the amount of motion in the field of view. The motion-detection system further comprising a buffer which stores a portion of the video segments occurring prior to a detection of motion and a portion of the video segments occurring after the detection of motion.
The motion-detection system also comprising a processor configured to locate in the buffer the oldest encrypted video segment which independently defines an image within the field of view. The processor further configured to transfer the oldest encrypted video segment and subsequent encrypted video segments from the buffer to a computer accessible storage medium.
Another aspect of the invention related to a motion-detection apparatus comprising a buffer that stores video segments which vary in size based on movement in a field of view. The motion-detection system further comprising a processor that is configured to locate in the buffer a prior video segment occurring before the detection of motion. The processor is further configured to transfer the prior video segment and subsequent video segments from the buffer to a computer accessible storage medium.
An additional aspect of the invention related to a motion-detection apparatus comprising a first means for temporarily storing video segments which vary in size based on movement in a field of view. The motion-detection apparatus further comprising a second means for locating in the buffer a prior video segment occurring before the detection of motion. The second means transferring the prior video segment and subsequent video segments from the buffer to a computer accessible storage means.
Another aspect of the invention related to an article of manufacture comprising a buffer module stored in a computer accessible storage media and executable in a processor. The buffer module configured to temporarily store video segments which vary in size based on movement in a field of view.
The article of manufacture further comprising a signal processing module stored in a computer accessible storage media and executable in a processor. The signal processing module is configured to locate in the buffer module a prior video segment occurring before the detection of motion. The processor is further configured to transfer the prior video segment and subsequent video segments from the buffer to a computer accessible storage medium.
Another aspect of the invention related to a method of detecting motion comprising the act of generating video data that represent a field of view. The method also comprising the act of encoding the video data to generate encoded video segments that vary in size based on the amount of motion in the field of view. The method further comprising the act of storing in a buffer, at least a portion of the video segments occurring prior to a detection of motion and at least a portion of the video segments occurring after the detection of motion.
The method also comprising the act of locating in the buffer the oldest encrypted video segment which independently defines an image within the field of view. The method further comprising the act of transferring the oldest encrypted video segment and subsequent encrypted video segments from the buffer to a computer accessible storage medium.
An additional aspect of the invention related to a method of storing video data comprising the act of storing in a buffer, video segments which vary in size based on movement in a field of view. The method also comprising the act of locating in the buffer a prior video segment occurring before the detection of motion. The method further comprising the act of transferring the prior video segment and subsequent video segments from the buffer to a computer accessible storage medium.
An aspect of the invention involves a computer system. The computer system includes a video input device to generate video data representing a field of view in front of the video input device, and a computer connected to the video input device. The computer includes a buffer and a video processing module. The buffer is configured to record a video clip of the field of view in front of the video input device. The video processing module is connected to the buffer and the video input device. The video processing module includes a video capture device to encode the video data in consecutive frames of varying size, and a signal processing module. The signal processing module processes the encoded video data in order to calculate an average value of the size of the encoded video data, and to generate an alarm signal if the average value exceeds a predetermined threshold value. The alarm signal indicates that sufficient motion has been detected in front of the video input device.
A further aspect of the invention involves a method for detecting motion with a computer system. Encoded video data is received from a video capture device. The encoded video data represents a field of view in front of a video input device, and includes frames of variable lengths. The length of a frame depends on motion within the field of view. An average value for the variable lengths of the frames is calculated and compared with a predetermined threshold value which defines no motion threshold in the field of view. If the average value is greater than the predetermined threshold value, an alarm signal is generated. The alarm signal indicates that the motion within the field of view is higher than in the no-motion threshold.
Another aspect of the invention involves a video processing module. The video processing module includes a video capture device and a signal processing module. The video capture device is configured to encode video data generated by a video input device. The encoded video data represents a field of view in front of the video input device. The signal processing module is connected to the video capture device and connectable to an interface module and a buffer. The signal processing module is configured to process the encoded video data in order to calculate an average value of the video data indicative of motion within the field of view in front of the video input device. If the average value is above a predetermined threshold value, an alarm signal is generated.